The present invention relates to a functional module which executes at least any one of video coding and video decoding based on ITU-T Recommendation H.264/AVC and a semiconductor integrated circuit including the functional module, and particularly to a technique which makes it easy to perform moving-picture or video parallel processing at intra-frame prediction based on H.264/AVC.
As a video coding system, MPEG (Moving Picture Expert Group)-based video coding system is now prevalent in the world. However, H.246/AVC approved as ITU-T (International Telecommunication Union, Telecommunication Standardization Sector) Recommendation H.264 and approved as International Standard 14496-10 (MPEG part 10) Advanced Video Coding (AVC) by ISO/IEC (International Organization for Standardization/International Electrotechnical Commission) is the latest international standard video coding.
A video coding technology based on Recommendation H. 246/AVC has been described in a non-patent document 1 (Thomas Wiegand et al, “Overview of the H.264/AVC Video Coding Standard”, IEEE TRANSACTIONS ON CIRCUITS AND SYSTEMS FOR VIDEO TECHNOLOGY, JULY 2003, PP. 1-19). The video coding based on Recommendation H.246/AVC comprises a video coding layer designed so as to express a video context effectively, and a network abstraction layer which formats the VCL representation of the video and provides header information in a manner appropriate for conveyance by a variety of transport layers and storage media.
A non-patent document 2 (GARY J. SULLIVAN et al, “Video Compression—From Concept to the H.264/AVC Standard” PROCEEDING OF THE IEEE, VOL. 93, No. 1, JANUARY 2005, PP. 18-31) has described that a video coding layer (VCL) based on H.246/AVC follows an approach called block-based hybrid vide coding. The VCL design comprises macroblocks, slices and slice blocks. Each picture is divided into a plurality of fixed-size macroblocks. The respective macroblocks include square picture areas of 16×16 samples as luminance components, and square sample areas corresponding thereto provided for two color-difference components respectively. One picture can contain one or more slices. Each slice is self-inclusive in a sense that it provides an active sequence and a picture parameter set. Since the slice representation can basically be decoded without using information given from other slices, syntax elements can be analyzed from a bit stream and the values of samples in a picture area. In order to obtain more complete decoding, however, several information from other slices are required to adapt a deblocking filter over a slice boundary. The non-patent document 2 has also described that since the respective slices are encoded and decoded independent of other picture's slices, they can be used in parallel processing.
On the other hand, in a system that deals with video codes, an image size has been made large-screen as in the case of a digital HDTV (High Definition Television) broadcast receiver, a digital video camera capable of imaging HDTV signals, or the like. An image coding device and an image decoding device need increasingly higher processing performance.